Problem with Model SM10A and extension cable

FAQ #1879 Updated September 20, 2012

Question:

I recently purchased a SM10A corded head-worn microphone. I plugged it into our PA system directly, and it worked fine. The short cable on the head set was way to short to run into the PA, so I added a standard XLR microphone cable as an extension for the head set. When doing this the signal is extremely weak. So I tried another cable that we know functions correctly and had the same results. Do I need to modify the connections on the XLR female connections on the head set? Any help that you can offer would be a blessing.. Also, the system that we have is all Mackie...A Mackie 16 channel board and a Mackie 1400i power amp, so we have more than enough watts.

Answer:

You should be able to run 1,000 feet of cable with little loss in signal. We have never heard of this problem.

We suggest a test with an ohmmeter. Without an extension cable, measure the dc resistance of the SM10A across XLR pins 2 and 3. It should be under 100 ohms.

Next measure across pin 2 and 1. It should be an open circuit (infinite ohms). Do the same across pins 3 and 1. The results should be the same.

Now add an XLR to XLR extension cable and do the same measurements. The results should be nearly identical. If not, there is a problem with the extension cable.

If the results are the same, the SM10 should work fine with the extension cable.

Last resort: Send the SM10A and an extension cable to Shure Service for investigation. Contact our Service Department at 800-516-2525 or 847-600-8699. Information concerning service, repair, parts and warranty of Shure products can be found at the following link: